Alright, let's solve this math problem step by step. First, we have the number 578. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 20. So, we're going to take the number 578 and add it to itself 20 times.
Step 1: 0 + 578 = 578
Step 2: 578 + 578 = 1156
Step 3: 1156 + 578 = 1734
Step 4: 1734 + 578 = 2312
Step 5: 2312 + 578 = 2890
Step 6: 2890 + 578 = 3468
Step 7: 3468 + 578 = 4046
Step 8: 4046 + 578 = 4624
Step 9: 4624 + 578 = 5202
Step 10: 5202 + 578 = 5780
Step 11: 5780 + 578 = 6358
Step 12: 6358 + 578 = 6936
Step 13: 6936 + 578 = 7514
Step 14: 7514 + 578 = 8092
Step 15: 8092 + 578 = 8670
Step 16: 8670 + 578 = 9248
Step 17: 9248 + 578 = 9826
Step 18: 9826 + 578 = 10404
Step 19: 10404 + 578 = 10982
Step 20: 10982 + 578 = 11560

So, 578*20 = 11560